Research Interests:

I am interested in understanding how insects interact with harmful and helpful microbes and the ecological and evolutionary forces shaping the insect immune system. As a vector biologist, I am also interested in finding ways to use this information to improve our ability to prevent the spread of vector-borne diseases. I work with Aedes aegypti, the mosquito vector of dengue virus, as well as Anopheles gambiae, the mosquito vector of the malaria parasite. I also work with Drosophila melanogaster, the humble fruit fly. My research interests focus on the following questions:

What factors control variability in the mosquito gut microbiota?

Field and laboratory sampling studies have shown that gut microbiota composition can vary between species, collection locales and even between individuals in the same population. Microbiota composition as well as total microbial load in the gut has also been shown to vary across developmental stages and as a result of changes in diet. This suggests that genetic, physiological and environmental factors could all play a role in shaping bacterial populations in the mosquito gut. My work focuses on understanding the mosquito genetic factors that contribute to variation in gut microbial load and microbiota composition. I take a multifaceted approach, combining high throughput methods (e.g. genome wide gene expression analysis, bacterial 16S high-throughput sequencing) with targeted molecular techniques (e.g. RNAi and qPCR) to quantitatively assess organism and population-level phenotypes.

Can we utilize natural mosquito pathogens to control vector borne disease?

Many of the mosquito-borne pathogens most detrimental to human health (e.g. malaria, dengue) do not seem to make mosquitoes sick. In fact, our understanding of natural bacterial pathogens of mosquitoes is quite incomplete. I am interested in identifying bacteria that are pathogenic to mosquitoes and investigating the ways in which these bacteria cause mosquitoes to become sick. I am primarily focusing on gut bacteria but am also interested in bacteria that cause systemic infections as well as viruses that are pathogenic to mosquitoes. Microbes that are naturally associated with mosquitoes represent an important source of novel control mechanisms and offer exciting opportunities to understand how mosquitoes interact with microbes in their environments. 

How does the immune system function and evolve in the context of a whole organism?

In addition to investigating mosquito-microbe interactions, I am also quite interested in understanding how insect immune defense interacts with development, reproduction and other processes essential to ensure reproductive fitness. Fighting infection can cause damage to the host or divert essential resources away from reproduction, and evolutionary theory predicts that these trade-offs can shape the evolution of immune defense. In some cases, these trade-offs act to maintain genetic variation in a population, especially if pathogen pressures are highly variable over time and space. In other cases, these trade-offs can drive changes in immune defense strategy, for example by favoring infection tolerance rather than resistance or by driving the the compartmentalization or specialization of immune responses (e.g. sexually dimorphic immunity). I am interested in exploring trade-offs in immune defense both to better understand how immune defense evolves, but also to more generally understand how trade-offs shape the evolution of complex, "whole-organism" traits.